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shaools
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Homework Statement
Two buckets of nails are hung one above the other and pulled to a roof by a rope. Each bucket of nails has a mass of 5.0kg. The action-reaction force between the buckets is 60N. Calculate the acceleration and the force applied by the worker lifting them up.
Given: (draw a fbd)
mA= 5kg
FB on A= 60 N
mB= 5kg
FA on B= 60 N [N]
ag = 9.8m/s2
Required:
acceleration(a) and force applied(Fapp)
Homework Equations
Fnet=ma
Fnet= Fapp+(-Fg)
The Attempt at a Solution
So, I need to calculate the net forces of one of the pails in order to find acceleration, because the pails have the same acceleration whether or not you consider them as separate objects or as apart of one.
Working with B:
Fnet= Fapp+(-Fg)
Fnet= FA on B+ (mB*ag)
Fnet= 60N + (5kg*-9.8m/s2)
Fnet= 60N + 49N
Fnet= 11N
a= Fnet/mB
a= 11N/5kg
a= 2.2m/s2
Now, I'm not sure how to approach calculating the applied force.
Does the force acting down on A include both the reaction force of 60N
I tried plugging in these values into the equation F=ma, so F=10kg*2.2m/s2=22N, but I think this value is the net force of both of the pails together and not just the applied force? The applied force should be much larger but I'm not sure how to find it.
The answer at the back of the textbook is 71N [N].
Help would be very appreciated, my classmates and I were stumped with this all class !